Large metal bins are commonly used for transporting and storing bulk granular materials which are vacuum discharged from the bin. Examples of bins that are usable for this purpose are shown in U.S. Pat. Nos. 2,648,428, 3,130,855 and 3,647,106, owned by the Assignee of the this application. Good examples of granular materials stored and transported in such bins are granular plastic materials such as polyethelene, polystyrene and PET.
One of the problems with conventional bins or cartons that are used for these purposes is that the bottom walls of the containers are flat for the purpose of achieving maximum volume in the interior of the container and it is difficult to fully evacuate all of the bin contents from such a container. Accordingly, it is an object of the present invention to provide a bin which is constructed to facilitate thorough vacuum discharge of the bin contents without sacrificing any of the interior capacity of the bin.
In the bin of this invention, a hollow body of generally rectangular shape is provided having a top wall, front and back walls, side walls and a bottom wall. An inlet opening is formed in the top wall and a discharge opening is formed in the front wall at the juncture of the front wall with the bottom wall and one of the side walls, the discharge opening being aligned with an internal corner of the bin at the juncture of the back and bottom walls with the one side wall.
As a result, when the bin is tipped upwardly about a generally horizontal axis located to one side of the bin and inclined with respect to the back and side walls the internal corner is located at an elevation below the remainder of the interior of the bin. As the bin is emptied, the bin contents are naturally directed into the internal corner by the bin walls. Thus, a suction tube can be directed inwardly of the bin straight through the discharge opening and into the internal corner for fully emptying such a bin of its contents.
A discharge tube in the bin is positioned so that it is parallel to the bottom wall and located in close proximity to the bottom wall in substantial alignment with the discharge opening and the internal corner. The discharge tube guides the suction tube into position at the internal corner to facilitate emptying of the bin.
The result is a bin which can readily be utilized to store and transport bulk material and which can also be manipulated at the point of use of the stored and transported material to facilitate vacuum discharge of the bin.